This study is a longitudinal, prospective investigation of the medical, environmental, and developmental correlates of fetal cocaine-exposure during the first two years of life and at follow-up ages of 4 and 6 years. Children are given standardized assessments of growth, cognitive, emotional, behavioral, language, and neuropsychological outcomes. Standardized questionnaires assess maternal psychological status, coping style, social supports, and exposure to violence. Data will be evaluated descriptively and through a series of MANOVAs/MANCOVAs with repeated measures and hierarchical multiple regression to describe the functioning of cocaine-exposed children at pre-school ages. Recent data analyses of infancts at one year of age has indicated that there are significant effects of early cocaine exposure, after control for other drugs and confounding factors, on infant mental development outcome and infant novelty performance as well as in early neurobehavioral and birth outcomes. Mothers who use cocaine are characterized as more psychologically disturbed, have experienced more violence, have lower intellectual ability, and poorer caretaking skills than controls. Approximately 100-150 subjects are enrolled each year. The GCRC psychometrist provides training to study personnel as well as conducting some of the developmental testing.